You can amortize the cost of geological and geophysical expenses
paid or incurred in connection with oil and gas exploration or development
within the United States. These costs can be amortized ratably over a 24-month
period beginning on the mid-point of the tax year in which the expenses were
paid or incurred. For major integrated oil companies (as defined in section
167(h)(5)), these costs must be amortized ratably over a 5-year period for costs
paid or incurred after May 17, 2006 (a 7-year period for costs paid or incurred
after December 19, 2007).

If you retire or abandon the property during the amortization
period, no amortization deduction is allowed in the year of retirement or
abandonment.